Skip to navigation

PCPro-Computing in the Real World Printed from

Register to receive our regular email newsletter at

The newsletter contains links to our latest PC news, product reviews, features and how-to guides, plus special offers and competitions.

// Home / Blogs

Posted on September 18th, 2009 by Sasha Muller

Intel Core i7 for laptops: first review

Core i7 mobile close-up

When it arrived on the desktop scene, Intel’s Core i7 levelled the opposition. With enough power to embarrass Intel’s own Core 2 architecture, not to mention AMD’s efforts, and coming at a cost that would make even a banker weep, Core i7 set the benchmark and set it high. Now, with the new Clarksfield range of processors it’s set to repeat the trick in the laptop market, and we’ve got our hands on a sample boasting the mid-range quad-core 1.73GHz i7-820QM.

The first processors to arrive will be quad-cores based on a 45nm process, with 32nm dual-core models following in early 2010. Intel has kept the quad-core line-up refreshingly simple too, with the 1.73GHz i7-820QM flanked on both sides by the 1.6GHz i7-720QM and the top of the range 2GHz i7-920XM. Unlike their Core 2 Quad predecessors, all four cores boast Hyper-Threading; a move that allows the processors to handle as many as eight separate threads at once.

A perfunctory look at the modest-looking clockspeeds is enough to leave the keen bystander a mite underwhelmed, but those figures don’t take any account of the ace resting up Core i7s sleeve – Turbo Boost.

Basically, if two or more cores are sitting unused, and the processor isn’t running too hot or drawing too much current, Turbo mode kicks in and ups the speed of the remaining cores. For the i7-820QM, this can take the stock speed of 1.73GHz up to a maximum of 3.06GHz, while the i7-720QM and i7-920XM push up to 2.8GHz and 3.2GHz respectively.

Core i7 CPU-Z


If you’re not bothered about the details and just want to know how fast it is, the answer is very, very fast. Take, for example, the fastest laptop we’ve ever seen: the Dell Precision M6400 Covet costs the same as a nice second-hand car (¬£4,100) and offers a Core 2 Quad QX9300 running at 2.53GHz, 8GB of DDR3 memory, a 7,200rpm hard disk and high-end Nvidia Quadro FX 3700M graphics.

That combination earned an overall score of 1.64 in our application-based benchmarks, so it was with some surprise that we saw our early i7 sample sidle up alongside with 1.59. It might not beat the Dell, but put it in perspective – the CPU is rated at just 1.73GHz, it has half the amount of RAM and a 32-bit OS installed (to the Covet’s 64-bit OS), an inexpensive 5,400rpm hard disk and a far more modest GT 240M Nvidia graphics chip. Whichever way you cut it, that’s an impressive achievement by the Core i7.

It’s the Turbo Boost feature that really impresses, though. In our testing it worked without a hitch, dynamically overclocking cores to suit single and multi-threaded applications, while disabling unused cores to keep power consumption within acceptable limits.

Attaching a power meter to the laptop shows the Turbo Boost function in action – stress one core to 100% load and the clockspeed rises to 3.06GHz while power consumption hovers around 58W. Fully load another core and the overclock reduces to 2.8GHz and the power consumption to 70W. Load either of the two remaining cores, and Turbo Boost keeps power consumption hovering around the 70W mark by lowering the overclock to a maximum of 2GHz. Finally, with all four cores flat out, it falls to a maximum of 1.73GHz with power consumption hitting peaks of 74W.

(Click on graphs to enlarge)

Core i7 for laptops - power consumption

2GHz Intel Core 2 Quad Q9000 - power consumption

2GHz Intel Core 2 Duo T6600 - power consumption

And, if you’re expecting all this power to turn your notebook into a mobile fireball, you’ll be pleasantly surprised. Our test sample was a modestly-proportioned 16in laptop, and with just a single vent at its side the i7-820QM idled at about 37 degrees centigrade, only hitting 77 degrees once the CPU was working flat out. Compare that to the 2GHz Core 2 Quad Q9000 in the recently reviewed Asus G71GX gaming beast, which idles at 50 degrees and peaks at 75 degrees, and the Core i7’s efficiency shines through.

As you might imagine, this efficiency helps improve battery life drastically. We rarely see quad-core laptops last more than a couple of hours even while sitting idle, but this one defied our expectations by lasting for over three and half hours with a bog-standard 4,800mAh battery. Push it to its limits, however, and our heavy usage test drained the battery in a mere 46 minutes.

Don’t forget, though, if you have to work on battery you can always engage Vista’s Power Saver mode – a measure which disables Turbo Boost and drops the CPU down to just 1.2GHz. In this scenario, with all four cores at full load, power consumption drops from 72W to a much more battery-friendly 52W – if you need all the benefits of multi-core computing, but longevity is important, too, then it’s a measure that can raise heavy usage battery life to a far lengthier 1 hour and 15 minutes.


Think it through briefly, and Core i7’s move to the mobile market might not make too much sense – indeed, combine huge power draw with massive heat output and you’ve pretty much nailed the absolute worst combination for the slimline confines of a laptop chassis.

However, Core i7 is a better match than anyone might have imagined. Several of its key features even seem to make more sense in a laptop than they do in a desktop PC, with Turbo Boost in particular making the perfect mobile match.

Price may yet prove to be a stumbling block, especially for the quad-core models, but going by the reasonable cost of Intel’s desktop-based Lynnfield platform upon which the mobile i7 platform is based, we can keep our fingers crossed that the forthcoming dual-core CPUs will bring all the i7’s benefits – Turbo Boost and Hyper-Threading included – to laptops of all prices, shapes and sizes.

Core i7 for laptops - 2D benchmarks

Core i7 for laptops - battery life tests

Tags: , , , ,

Posted in: Hardware, Just in, Random


Follow any responses to this entry through the RSS 2.0 feed.

You can skip to the end and leave a response. Pinging is currently not allowed.

43 Responses to “ Intel Core i7 for laptops: first review ”

  1. Nicomo Says:
    September 18th, 2009 at 7:15 pm

    Nice move, with a low price intel will certainly own the laptop market outright.

  2. Chad Says:
    September 18th, 2009 at 10:26 pm

    This may just be the review of the year, considering sales of laptops have now outpaced desktops and (beside SSDs) this is the laptop technology everybody has been waiting on for over a year now. I was pleasantly surprised to see a single can gets overclocked to 3 ghz, the current technological limit (because transistors need a certain amount of time to reset).

    The only questions now (with hyperthreaded dual core 32 nm Arrandale a few months away) are: how often are people going to use that 3rd and 4th core on the Clarksfield? And with the power constraints on a laptop (throttling 3rd and 4th cores below 2 ghz) and programs needing to be specifically written for that many threads (5-8 thread for Clarksfield), how much benefit do the third and fourth cores really even give you?

  3. Chad Says:
    September 19th, 2009 at 1:31 am

    I guess the other question in Clarksfield vs Arrandale would be: What would you rather have the extra die space used for? A couple of underclocked cores that you will rarely ever use unless you have software specifically programed to use them, or a very weak but efficient integrated graphics core (much weaker than even geforce 9400m based on old tech) that won’t even be used when the laptop is plugged in because it will then turn off and switch to a dedicated graphics card.

  4. Hothot Says:
    September 19th, 2009 at 1:41 am

    I’d be far more interested in something like a 2.2Ghz dual core i7 with turbo mode to about 3ghz.

    Then you have a laptop that doesn’t need to be plugged in for its entire life which is still more than powerful enough for everyday tasks.

  5. NukemHill Says:
    September 20th, 2009 at 12:53 am

    How does this compare to the power consumption and heat characteristics of the 2GHz Core Duo that is in the original 15″ Macbook Pro? I find that my MBP runs uncomfortably hot, and am wondering if more recent chips are better or if I’m just going to have to deal with it.

  6. MrBill Says:
    September 20th, 2009 at 5:45 am

    Kinda strange to be going “yay Intel for making a chip that only runs at half speed!” A few years ago, if anyone had tried selling a chip with the instructions “if you run this at its rated speed, it will melt,” they would have been tarred and feathered. And they were, with the P3 1GHz.

  7. Fred Says:
    September 20th, 2009 at 5:44 pm

    This article had so many holes my mind is still spinning. Comparing only laptops that shoe horned in a core2 quad and saying what great battery life this things gets is just absurd. Anything less than 4 hours with light usage is garbage. Also it only runs at 1.2 GHz during that time?

    This thing would burn you for the very short amount of time you could use it if put inside a Macbook Pro. Lets see a review by someone that cares about something other than portable gaming rigs that must remain plugged in at all times.

  8. NukemHill Says:
    September 20th, 2009 at 11:57 pm

    I guess the i5 (which I’d heard about before) is what will become the real notebook chip. I’d thought maybe the i7 discussed above was something new that made the i5 unnecessary, but that’s clearly not the case. I did a little digging, and the original Core Duo was 25 Watts. Yikes. And it’s hot. I can’t believe this version of the i7 is really being marketed as “portable”.


    I guess I’m going to have to wait until next Spring for the i5. Sucks.

  9. Hok Says:
    September 21st, 2009 at 12:49 am

    I hope this I7M will available on road warrior notebook. Not just monster gaming that is too big to cary arround.

  10. milliganp Says:
    September 21st, 2009 at 7:41 am

    I’m bemused by some of the negative feedback. At idle the power consumption is similar to a well designed dual-core notebook and there’s lots of power both for normal PC apps and the more exotic multi-core stuff. With the increased use of virtualisation technology >2 core processors do find a use.
    There are plenty of users who want a laptop that’s almost as good as a desktop -and it’s not just gamers. Well done Intel (with Windows 7 my natural hatred of Wintel is being sorely tried;)

  11. Clostnix Says:
    September 21st, 2009 at 8:37 am

    Hmm, Intel always better than AMD. I think consumer will buy this products than competitor products. Intel marketing guerilla will kill any obstacle in retail and keep competitor products hiding. It is a lawfully conducts and Intel will crush their competitor.

  12. James Says:
    September 21st, 2009 at 9:14 am

    2 cores running flat-out at 2.8GHz is sufficient, especially if 4 cores reduce everything to 1.73GHz! The dual core chip will therefore be the sweet spot for real-world use.

  13. Host1Plus Says:
    September 21st, 2009 at 9:37 am

    This is monster, but I will wait for AMD answer to buy intel i7 at lower price, xe xe :)

  14. Joe Says:
    September 21st, 2009 at 11:48 am

    For a typical user it seems like the power consumption at max load would not be the relevant number, since the i7 would finish a task faster than a core2duo. What I want to know is whether doing the same task costs more total energy with one chip or the other. Is that kind of ‘efficiency spec’ included in the final graph? If not, which one of these architectures is more power efficient? -Joe

  15. Martin Says:
    September 21st, 2009 at 1:20 pm

    Am I the only one who thinks that it is wierd that the processor name is intel core i5??? second image…

  16. Scott Says:
    September 21st, 2009 at 1:23 pm

    Apparently all you people whining about unused cores and specialized programs don’t understand multitasking… yes you can run more than one program… shocking I know. I have the i7 in my desktop and it’s awesome… imagine a world where your Core 2 Duo didn’t lag occasionally when you had too many things open or a program was updating in the background. And that’s i7.

  17. CyberPowerUK Says:
    September 21st, 2009 at 1:25 pm

    Laptop with a proper i7 (x58/LGA1366) have been around for a while:

  18. SiliconAddict Says:
    September 21st, 2009 at 2:12 pm

    I yearn for the day when people can show up on a discussion thread and know what they are talking about. The people that are freaking out about AHHH HOT or about the performance of a 1.2Ghz system don’t get the fact that multiple cores will be turned off, or they will be scaled. So a Win7 system at 1.2Ghz will be able to accomplish what was being done on a 2.0Ghz system just as easily due to the system knowing how to work with quad cores. RTFA people and grow a clue: the system scales to what is being done at the time and THAT is why this is going to be huge.

  19. SiliconAddict Says:
    September 21st, 2009 at 9:13 pm


    Yah right. I’ve worked with desktop processors crammed into laptops. No way in heck, never again. There is a reason most of those systems are wind tunnels. The failure rate on those systems is also drastically higher for obvious reasons.

  20. Vin Says:
    September 23rd, 2009 at 10:55 pm

    I don’t get whats so good about 1H15M of battery life… I hope the new dell studios have a better battery life than this..

  21. Shiranai Says:
    September 24th, 2009 at 11:15 am

    A BATTERY-FRIENDLY 52W in energy saving mode? LOL? Thats about as much as my whole Core2Duo notebook consumes – with 100% load. I’d say Core i7 is one hell of a battery eater…

  22. non Says:
    September 24th, 2009 at 8:02 pm

    @shiranai that was exactly what i was thinking. 52 W on the lowest is kind of a joke considering this called a notebook. I would like it much better to see such cpu in desktop computers like the Mac mini or such.

  23. Sasha Muller Says:
    September 24th, 2009 at 9:41 pm

    I probably should have explained it a little more clearly.

    That is 52 watts with all eight (all 4 physical and all 4 logical) cores pegged at 100%, and those processor cores running at 1.2GHz apiece.

    As you can see in the graphs, idle consumption is nearer 25 watts.

  24. Alex4life Says:
    September 27th, 2009 at 5:31 am

    Negative reviews from people who can’t process information properly need to be deleted, with the most recent examples being the 2 blokes who failed to look on the bar graph what the idle power consumption is for the Core i7. Excellent review, I am happy beyond belief that I waited for the Intel Core i7 processor and decided to axe the thought of getting a laptop with Intel Core 2 Quad. I can multitask when I need to with video encoding and calculations, and when I’m barely doing anything the processor will adjust accordingly.

  25. Efficiency Says:
    September 27th, 2009 at 5:38 am

    Sasha, was the power measurement taken from AC? In other words did you take into consideration the efficiency of the adapter. If the adapter is only 80% efficient then 50W would be the equivalent of 40W DC or what you might expect running of the battery.

    Interesting how at full load a single core @3.06 draws a lot less than 2 cores @2.8. I wonder why Intel didn’t make the single core turbo boost higher than 3.06

  26. jeffreybaks Says:
    September 27th, 2009 at 7:53 am

    anythiing new to fiddle with is mostly good thing in terms of computers. I think the turbo boost is a good idea and has implemented extreamly well. The power saving 1.2 ghz mode is even better. I could only imagin geting a new alienware and having battery life last more then an hour as the new m15x are equiped with the 2.0 ghz i7 920QM processors.

  27. TonyP Says:
    October 20th, 2009 at 9:12 pm

    In my attempts to educate myself regarding processors for laptops, this has been the most useful piece I have read. Thanks.

  28. Kaushik Says:
    October 28th, 2009 at 3:47 pm

    hey ppl, quad cores r really the trend, and new games and softwares (Like GTA IV for ex) are designed to use the latest hardware technologies like Hyper Threading and multi-core processes so there’s no question that the remaining 2 cores wont be used. As far as battery life’s concerned i think i’ll buy a laptop with 12 cell Li-ion or an additional battery battery to do the job as i’m a chess Player and i do really need the power of quad core to analyze my games and portability of a laptop to carry wherever i go to tournaments!! HURRAY!!

  29. safaesf Says:
    November 9th, 2009 at 2:21 am

    12 cell notebook battery…o_O U gotta tel me where to find that

  30. Joseph Says:
    November 12th, 2009 at 4:53 pm

    12-cell additional battery in the hp pro line

  31. ramya Says:
    December 12th, 2009 at 6:53 pm

    i jus wanted to know if this will heat up my computer, n will the bettery life be good in my dell studio 15…

  32. lll Says:
    December 18th, 2009 at 9:39 am

    top edhardy womens intimate

  33. stepney Says:
    December 21st, 2009 at 3:11 pm

    i am just waiting for prices to go down for core i7-920XM. i would love to see my next laptop with this cpu.

  34. jon m Says:
    January 11th, 2010 at 1:05 am

    you say this is a powerful processor, yet, i fear this is merely hubris awaiting the inevitable nemesis that is the installation of an hp printer software suite… “look on my works, ye mighty, and despair…”

  35. Ninad Says:
    January 21st, 2010 at 9:51 am

    Just bought the HP core i7 1.6 Ghz with 4 GB DDR2 ram and 1GB nvidia graphics for just AUD 1070..thats under 1000 USD..what a bargain :) its very powerful..just wanted to see what is turbo..didnt know when i bought it..and the salesman didnt know either lol

  36. dagenham Says:
    January 28th, 2010 at 1:35 am

    i would like to have i7 920xm in my next notebook but its too pricy @ de moment.
    any comments from 920xm users regarding performance and battery life and screen size.
    would i7 920xm ever appear in 14 inch notebook? your thoughts

  37. dizi izle Says:
    May 10th, 2010 at 3:15 am

    thank you

  38. kirod Says:
    June 28th, 2010 at 9:02 am

    i just bought the i7 820 with 6gb ram dell laptop. waiting for the delivery. i hope it will increase the battery life as well as backup time :)

  39. laptops Says:
    April 6th, 2011 at 7:38 am

    I have to agree with Nicomo’s comment on this one. This is such a smart move for Intel to do.

  40. tax lawyer lancaster pa Says:
    May 20th, 2012 at 3:59 am

    When I initially commented I clicked the -Notify me when new feedback are added- checkbox and now each time a remark is added I get four emails with the identical comment. Is there any means you may remove me from that service? Thanks!

  41. Discount coupon code Says:
    February 20th, 2013 at 9:37 pm

    Wonderful goods from you, man. I have understand your stuff previous to and you are just too excellent.
    I really like what you have acquired here, certainly like what
    you are saying and the way in which you say it.

    You make it enjoyable and you still take care
    of to keep it wise. I can not wait to read much more from you.
    This is really a tremendous web site.

  42. Coldwater creek coupons Says:
    February 25th, 2013 at 7:11 pm

    I’m not sure exactly why but this site is loading incredibly slow for me. Is anyone else having this issue or is it a problem on my end? I’ll check back later and
    see if the problem still exists.

  43. Says:
    February 26th, 2013 at 2:02 pm

    What’s up, yeah this piece of writing is genuinely fastidious and I have learned lot of things from it about blogging. thanks.


Leave a Reply

Spam Protection by WP-SpamFree

* required fields

* Will not be published






Your email:

Your password:

remember me


Hitwise Top 10 Website 2010